The Russo-Japanese War was a conflict between Russia and Japan that started in the year $1904$. Let $x$ represent any year. Write an inequality in terms of $x$ and $1904$ that is true only for values of $x$ that represent years before the start of the Russo-Japanese War.
Since the war started in ${1904}$, we want an inequality that represents years before ${1904}$. ${x}$ represents years, so we want this to be less than ${1904}$. The inequality can be written ${x} < {1904}$ or ${1904} > {x}$.